Fix #85, crop.cpp lint
Fix #85, crop.cpp lint

lucadelu/PDAL,mtCarto/PDAL,Sciumo/PDAL,radiantbluetechnologies/PDAL,jwomeara/PDAL,verma/PDAL,radiantbluetechnologies/PDAL,lucadelu/PDAL,verma/PDAL,Sciumo/PDAL,verma/PDAL,DougFirErickson/PDAL,mtCarto/PDAL,mpgerlek/PDAL-old,verma/PDAL,Sciumo/PDAL,boundlessgeo/PDAL,jwomeara/PDAL,verma/PDAL,mpgerlek/PDAL-old,mtCarto/PDAL,lucadelu/PDAL,DougFirErickson/PDAL,Sciumo/PDAL,mpgerlek/PDAL-old,radiantbluetechnologies/PDAL,jwomeara/PDAL,mpgerlek/PDAL-old,boundlessgeo/PDAL,mtCarto/PDAL,DougFirErickson/PDAL,verma/PDAL,verma/PDAL,lucadelu/PDAL,DougFirErickson/PDAL,boundlessgeo/PDAL,jwomeara/PDAL,boundlessgeo/PDAL,radiantbluetechnologies/PDAL